Just go to Google maps in your area and search pressure washing / cleaning
At least you’ll see who’s on Google
If you going to work for someone you should work for someone far away, that way you can be honest about your intentions and he won’t see you as competition, OR work for the largest commercial company in your area, he won’t see you as competition
Edit: also here’s a pwra/wcra link showing all members
https://shopwindowcleaningresource.com/association/members-map.html